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| n | a(n) |
|---|---|
| 1 | 0 |
| 2 | 1 |
| 3 | 3 |
| 4 | 5 |
| 5 | 10 |
| 6 | 21 |
| 7 | 45 |
| 8 | 114 |
| 9 | 330 |
| 10 | 1045 |
| 11 | 3623 |
| 12 | 13545 |
| 13 | 53597 |
| 14 | 223085 |
| 15 | 969159 |
[0,1,3,5,10,21,45,114,330,1045,3623,13545,53597, 223085,969159] |